JPS6190134A - Liquid crystal panel - Google Patents

Abstract

PURPOSE:To improve an excellent aging resistance of the titled panel by forming a film comprising a reaction product of indium acetylacetonate, a nylon and an epoxide resin as a main component on a substrate. CONSTITUTION:The orientation controlled film 3 is formed by vapor-depositing an electrode 2 comprising a transparent film contg. stannic oxide and indium oxide as a main component on the substrate 1 composed of an inorg. glass and a plastic film etc. and by coating the substate with an alcoholic solution of indium acetylacetonate adding indium octylic acid, the nylon and the epoxide resin, and then by heating and drying the obtd. film. The titled liquid crystal panel is prepared by enclosing the liquid crystal material 7 together with a gap material 6 which is used to maintain a space between the substates 1 into the space between the substrates 1 providing the electrode 2 and the orientation controlled film 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal panel used in various displays, etc., in which a liquid crystal substance is sealed between a pair of substrates.
In particular, the present invention relates to an alignment control film formed on a substrate surface to adjust the alignment of liquid crystal molecules in such a liquid crystal panel.

[Prior Art] In general, a liquid crystal panel has a liquid crystal material sealed between a pair of substrates, at least one of which is transparent, provided with electrodes mainly made of tin oxide or indium oxide, so that a voltage can be applied between the electrodes. It has become. This LCD panel is
It is widely used for various displays, and the orientation of liquid crystal molecules is adjusted to improve the clarity of displayed images. As a means for adjusting the alignment of liquid crystal molecules, it is known to form an ultra-thin film, ie, an alignment control film, on a substrate surface, which has an effect of controlling the alignment M of liquid crystal molecules.

Conventionally, as the above-mentioned alignment control film, a film formed of a reaction product of nylon, epoxy resin, and organic titanate is known (Japanese Patent Laid-Open No. 58-142
No. 20). This alignment control film is prepared by applying a mixed solution of the above three to a substrate, and then heating it at a relatively low temperature (130 to 150°C).
), it has the advantage of being applicable even when a plastic substrate is used, which is excellent in mass production, or when a switching element that is sensitive to heat is installed.

However, according to experiments conducted by the present inventors, when a liquid crystal panel is formed with the above-mentioned alignment control flu, there is a problem in that it is difficult to obtain sufficient aging resistance. If the aging resistance is insufficient, the alignment of liquid crystal molecules will be disturbed over time, resulting in blurred images and a decrease in sharpness.

[Problems to be Solved by the Invention] The present invention can be formed by heating at a relatively low temperature that can sufficiently withstand even when the substrate is made of plastic or when a switching element that is sensitive to heat is installed. The problem to be solved is to obtain a liquid crystal panel that exhibits aging resistance.

[Means to solve the problem] The first measure taken to solve the above problem is:
The object of the present invention is to provide a liquid crystal panel (hereinafter referred to as the "first invention") in which a film mainly composed of a reaction product of indium acetylacetonate, nylon, and epoxy resin is formed as an alignment control film on a substrate surface. The second means is a liquid crystal panel (hereinafter referred to as the "second invention") in which a film mainly composed of nylon and epoxy resin is formed as an alignment control film on the substrate surface using indium acetylacetonate as a coupling agent. That is to say.

[Function] In the Mokoku invention, nylon has an excellent alignment effect, and indium acetylacetonate and epoxy resin have a so-called reinforcing agent effect that forms a stable film without impairing the alignment effect of nylon. I will do it. Furthermore, indium acetylacetonate also has a function that supplements the orienting effect of nylon.

Although the bonding state of these champions is not necessarily clear, the present inventors speculate as follows. That is, while it is known that nylon and epoxy resin undergo condensation polymerization,
Since indium acetylacetonate and nylon are difficult to react directly, first, nylon and epoxy resin undergo polycondensation, and indium acetylacetonate is bound to the epoxy resin bound to nylon in a form similar to a frontal bond. It is thought that it stabilizes the whole thing. Since these reactions can be achieved at a relatively low temperature, a stable orientation control film with excellent orientation can be obtained by heating at a relatively low temperature.

On the other hand, in the second invention, indium acetylacetonate, which is a coupling agent, binds to a film whose main component is a reaction product of nylon and epoxy resin, which is an alignment control film, and stabilizes the entire film on the substrate. It is thought that it has become established.

Moreover, in this case, each component is considered to have the same effect as in the first invention, except that indium acetylacetonate acts as a coupling agent.

[Example] First, to explain the second invention, in FIG.
2 is a substrate, 2 is an electrode made of a transparent conductive film provided on the substrate 1, 3 is an alignment control film, 4 is a sealing material layer, 5 is a vertical conductive layer, 6 is a gap agent, and 7 is a liquid crystal material.

The substrate l is at least partially transparent, and in addition to inorganic glass,
For example, plastic films such as aromatic heat-resistant polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyethersulfone, polysulfone, polycarbonate, cellulose acetate, diene rubber, acrylic resin, and urethane resin can be used.

When the substrate 1 is made of a plastic film, the mass productivity of the liquid crystal panel is improved, and in particular, the alignment control film 3, which will be described later, is useful when the substrate 1 is made of a plastic film.

The electrode 2 provided on the substrate 1 is a transparent conductive film mainly made of, for example, tin oxide or indium oxide, and is attached to the substrate 1 by vapor deposition, low-temperature sputtering, CvD, or the like. Further, the substrate 1 is provided with a coating as an alignment control film 3, which is mainly composed of a reaction product of indium acetylacetonate, nylon, and epoxy resin, which will be described later.

A capping agent 6 for maintaining the distance between the substrates 1 is provided between the substrates 1 provided with the electrodes 2 and the alignment control film 3.
A liquid crystal material 7 is also sealed therein.

Next, orientation control JIS! 3 will be explained in more detail. .

Indium acetylacetonate may be used with the addition of indium octylate, and indium octylate may be included in the coating of the reaction product of nylon and epoxy resin. By adding indium octylate, the orientation control effect can be improved. This indium octylate has the general formula In+OR)
3 (where R represents an alkyl group), specifically In(OC2H
5) 3, In” (003H7) 3, In (OC
5Hll) 3, etc., and those in which R=C3H7 are particularly preferred from the viewpoint of manufacturing and handling. In addition, the ratio of indium acetylacetonate and indium octylate in the alignment control film 3 is 5 to 10:0.2 to 1 (weight ratio), and especially 8:0.3 (weight ratio) from the viewpoint of solution stability. )
Preferably before and after.

As the nylon, a nylon copolymer is preferred from the viewpoint of ease of handling, and specific examples include 6-nylon, 8.6-nylon, and 12-nylon, and among them, 12-nylon is preferred from the viewpoint of ease of film formation. .

Further, the nylon is preferably an alcohol-soluble nylon copolymer from the viewpoint of workability in film formation. In addition, especially when the substrate 1 is made of plastic or when a switching element that is sensitive to heat is installed, the melting point is about 80 to 130'C so that a film with excellent orientation control ability can be obtained by heating at as low a temperature as possible. It is preferable to use nylon.

Epoxy resins include glycidyl ether type, glycidyl ester type, bisphenol type, glycidyl amine type, cycloaliphatic type, linear aliphatic type, etc. Bisphenol type A is preferred. In particular, a liquid material having a CH3 OH-CH2) of 0 to 3 is preferable because it has a sufficient ability to control the orientation of the film.

indium acetylacetonate) (A), nylon (B)
), the component ratio of the epoxy resin (C) in the orientation control film 3 is:
It is preferable that A/B/C=5 to 30/10 to 50/1-10 (in terms of weight ratio, A is calculated as In203), and optimally A/B/C is about 18/3/2. It is also preferable to include indium octylate as component A in the above ratio.

Next, the second invention will be explained with reference to FIG. 2. As shown in the figure, an alignment control film 3 is formed on a substrate l with a coupling agent 8 interposed therebetween. The coupling agent 8 is indium acetylacetonate, and the alignment control film 3 is a film mainly composed of a reaction product of nylon and epoxy resin. Indium acetylacetonate, nylon, and epoxy resin are each explained in FIG. This invention is similar to the first invention. Further, as in the first invention, indium octylate may be added to indium acetylacetonate. still,
In FIG. 2, members having the same reference numerals as in FIG. 1 represent the same members as in FIG.

As mentioned above, indium acetylacetonate (A)
When the coupling agent 8 is used as the alignment control film 3 and the reaction product coating 1112 mainly composed of nylon (B) and epoxy resin (C) is formed, the ratio of these components is A.
/B/C=30-5015-15/250-300 (weight ratio A is calculated as 111203),
Optimally, A/B/C=35/11/280.

, the formation of each alignment control film 3 in the first and second inventions is as follows:
This can be easily done as follows. That is, in the first invention, indium acetylacetonate, nylon, and epoxy resin are dissolved in a solvent and this solution is applied to the surface of the substrate l, and in the second invention, indium acetylacetonate is dissolved in a solvent. On the other hand,
The alignment control film 3 can be formed by separately dissolving nylon and epoxy resin in a solvent, sequentially applying this solution to the surface of the substrate 1, and then heating and drying each.

Examples of the solvent include alcohols such as ethanol, methanol, butanol, isopropyl alcohol, propatool, ketones such as acetone methyl ethyl ketone and dimethyl ketone, cyclic ethers such as tetrahydrofuran and dioxane, and mixtures thereof. The material is selected in consideration of solubility with the components, non-reactivity with each component, evaporability during film formation, etc. The ratio of dissolved components as solids to the solvent is preferably 0.1 to 5% by weight, and preferably 3% by weight or less in order to obtain particularly excellent alignment performance and uniformity of the film.

The solution can be easily applied to the substrate 1 by a dipping method or a spraying method. Drying after coating on the substrate 1 is preferably carried out at 60 to 150°C for about 30 to 300 minutes. From the viewpoint of preventing partial alignment defects, it is particularly preferable to dry at 60 to 150°C.
00 minutes is appropriate. After drying, dry it with cotton cloth etc. for 20 minutes.
~200 g/cm2. Optimally, it is preferable to perform the rubbing under a static pressure of about 100 g/cm 2 because the alignment control film 3 with even better alignment can be obtained.

Orientation system g in Mizutoshi- and the second invention! Jffi3 is
Since it can be easily formed as described above and does not require a vacuum process, patterning (etching, copying) process, or printing process, continuous production is easy.

Example 1 A solution having the following composition was applied to a substrate comprising a polyethylene terephthalate film with a thickness of 100 pL and a transparent conductive film mainly composed of indium oxide as an electrode.
It was dried at ℃ for 80 minutes. Further, the electrodes were attached using a low-temperature sputtering device while keeping the film surface temperature below 120°C.

(Solution) Ethanol 10gIn-(AA)
Solution 30g 12-Nylon copolymer (trade name: Diamid Daicel Chemical Industries Co., Ltd. 0.1g) Molecular weight 1000-1500 Melting point peak 105°C Bisphenol A type epoxy (25°C) Epoxy equivalent 184-184 However, In-(AA ) The solution was obtained by dissolving In-('AA) at 2.5% by weight (in terms of In203) in the following solvent system. This solution was used because In(AA) would be hydrolyzed if left in the air.

Solvent system n-butanol 8.6% isopropyl alcohol 12.0 7r acetylacetone 1,2 tt propionic acid
14.4 //Ethanol
19.2 //Turpentine 3.6
//Ethyl acetate 40. Q/
/ After applying the above solution to the substrate and drying it, 100
Rubbing was performed in one direction under a pressure of g/cm2, two of these substrates were stacked so that the upper and lower rubbing directions were perpendicular, and the gap was filled with Loche RO-TN-819 liquid crystal (pyrimidine-based Δε〉0 nematic liquid crystal). , and a liquid crystal panel. Table 1 shows the results of the durability test of this liquid crystal panel.

Example 2 A liquid crystal panel was manufactured in the same manner as in Example 1, except that the following solution (1) was applied to a substrate, and then solution (2) was applied in layers and dried at 120° C. for 120 minutes. Table 1 shows the results of the durability test of this liquid crystal panel.

(Solution ■) Butanol 10g In(AA) solution 0.73In(OC3H7) 3 solution 0.02g (Solution H) Ethanol/Methyl ethyl ketone 8g/2g Nylon 0.003g Epoxy resin 0.002g However, In(AA) solution,
The same nylon and epoxy resins used in Example 1 were used. In addition, In-(QC+a H
7) Solution 3 contains 2.5% by weight (In2) in the following solvent system.
It is obtained by dissolving In(Ol:3H7)3 (in terms of 0B). This solution was used for In)0(:3H
7) This is because 3 hydrolyzes when left in the air.

Solvent system n-butanol 16% by weight Isopropyl alcohol 20〃Acetylacetone
2 // Propionic acid 2
4〃Ethanol 321! Turpentine oil 6 Comparative Example 1 A liquid crystal panel was produced in the same manner as in Example 1 except that In-(AA) used in Example 1 was replaced with tetraoctyl titanate. Table 1 shows the results of the durability test of this liquid crystal panel.

Comparative Example 2 A liquid crystal panel was produced in the same manner as in Example 2 except that In(AA) used in Example 2 was replaced with tetraoctyl titanate. Table 1 shows the results of the durability test of this liquid crystal panel.

Table 1 Uniform orientation Δ: Partial alignment failure (domains, rubbing lines, etc.)
×: Not horizontally oriented or oriented leg 0% or less, the evaluation is:
A liquid crystal panel was placed between two polarizing plates arranged so that the polarization directions were perpendicular to each other, and the alignment state of the liquid crystal panel by transmitted light was visually observed from the normal direction to the panel.

[Effect of the Invention 1 According to the present invention, a liquid crystal panel with extremely excellent durability can be obtained. Moreover, the alignment control film of the liquid crystal panel exhibits the above-mentioned durability and excellent alignment control effect when heated at low temperature, so it can be used even when a plastic substrate or a switching element that is sensitive to heat is installed, and it can be used in the production of liquid crystal panels. It is something that can improve your sexuality.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an example of a liquid crystal panel according to the second invention, and FIG. 2 is a longitudinal sectional view showing an example of a liquid crystal panel according to the second invention. l: substrate, 2: electrode, 3: alignment control film, 4: sealing material layer, 5: upper and lower conductive layers, 6: gap agent, 7: liquid crystal substance, 8: coupling agent.

Claims (1)

[Scope of Claims] 1) A liquid crystal panel characterized in that a film mainly composed of a reaction product of indium acetylacetonate, nylon, and epoxy resin is formed as an alignment control film on a substrate surface. 2) The liquid crystal panel according to claim 1, wherein the substrate is a plastic film. 3) The liquid crystal panel according to claim 1, wherein the reaction product contains indium octylate. 4) The liquid crystal panel according to claim 1, wherein the nylon is a nylon copolymer. 5) The liquid crystal panel according to claim 4, wherein the nylon copolymer contains 12-nylon. 6) The liquid crystal panel according to claim 4, wherein the nylon copolymer is alcohol-soluble. 7) The liquid crystal panel according to claim 1, wherein the nylon has a melting point peak of 80 to 130°C. 8) The liquid crystal panel according to claim 1, wherein the epoxy resin is a bisphenol type. 9) The liquid crystal panel according to claim 8, characterized in that it is a bisphenol A type epoxy resin. 10) The liquid crystal panel according to claim 9, wherein ▲ where ▲ includes a mathematical formula, chemical formula, table, etc. ▼ in the bisphenol A type epoxy resin is 0 to 3. 11) A liquid crystal panel characterized in that a film mainly composed of nylon and epoxy resin is formed on a substrate surface as an alignment control film using indium acetylacetonate as a coupling agent. 12) The liquid crystal panel according to claim 11, wherein the substrate is a plastic film. 13) The liquid crystal panel according to claim 11, wherein the coupling agent contains indium octylate. 14) The liquid crystal panel according to claim 1, wherein the nylon is a nylon copolymer. 15) The liquid crystal panel according to claim 14, wherein the nylon copolymer contains 12-nylon. 18) The liquid crystal panel according to claim 14, wherein the nylon copolymer is alcohol-soluble. 17) The liquid crystal panel according to claim 11, wherein the melting point peak of nylon is 80 to 130°C. 18) The liquid crystal panel according to claim 11, wherein the epoxy resin is a bisphenol type. 19) The liquid crystal panel according to claim 18, characterized in that it is a bisphenol A type epoxy resin. 20) The liquid crystal panel according to claim 19, characterized in that the value ▲of the bisphenol A type epoxy resin is 0 to 3.